test run fail

[stratcat88]

mornin men.1985 5.7 mercruiser,alpha one here again.after putting engine all back together we ,my wife and i took her too the boat ramp for the first time yesterday. i had to pump the throttle about 50 times to get it to start. had a couple of leaks,water so i tightend a few hoses and we were good to go. idled out to icw and gave it a little throttle and it was up around 1500 rpms. and that was it. the more throttle i gave her it would do nothing. we went about a mile like that and turned around and went back to the ramp.got to ramp, sat there for 15 min, would not start. so i pumped the throttle 50 times and it fired up. went to put it in forward and it would not go. the button will not push out automatically.only good thing about first test run,did not have to call sea tow. i cleaned out the filter on carb.new fuel/water sep. good fuel pressure to carb. the things i did not do to engine before test run, compression test, time engine, heads rebuilt, new manifolds,risers, plugs,tach,ign.coil, and alot of blood,sweat,and screaming.could use some advice, thanks.

 

[gm280]

Re: test run fail

mornin men.1985 5.7 mercruiser,alpha one here again.after putting engine all back together we ,my wife and i took her too the boat ramp for the first time yesterday. i had to pump the throttle about 50 times to get it to start. had a couple of leaks,water so i tightend a few hoses and we were good to go. idled out to icw and gave it a little throttle and it was up around 1500 rpms. and that was it. the more throttle i gave her it would do nothing. we went about a mile like that and turned around and went back to the ramp.got to ramp, sat there for 15 min, would not start. so i pumped the throttle 50 times and it fired up. went to put it in forward and it would not go. the button will not push out automatically.only good thing about first test run,did not have to call sea tow. i cleaned out the filter on carb.new fuel/water sep. good fuel pressure to carb. the things i did not do to engine before test run, compression test, time engine, heads rebuilt, new manifolds,risers, plugs,tach,ign.coil, and alot of blood,sweat,and screaming.could use some advice, thanks.

Pumping the throttle 50 times is a key to a lot of your problems. Sounds like your carb is in need of a rebuild. And it also sounds like the choke isn't working either. So before trying again, rebuild the carb and make sure the choke is operational. Then check the compression and timing as well. All these things effect your drivability... Do those things and post back here with your results and numbers... These forums will get you straighten out and running again.

 

[Maclin]

Re: test run fail

Can you look down the carb throat while pumping the throttle lever on the carb (or have a helper move the main throttle-only lever)? 50 pumps is way overkill, 2 or three should be all that is needed IF there is fuel in the carb AND the accelerator pump in the carb is working. A good solid stream of fuel should spray into the carb bore as the throttle is moved, does not have to be moved quickly. If nothing comes out at first or just drops come out then the carb needs fuel or the accelerator pump is not working and the carb needs rebuilt.

If a good stream is coming out then 50 pumps is probably flooding it. When it is hard to start open the throttle up all the way and see it if starts that way, be ready to move the lever back. That is one way to try clear a flooded condition.

You should pull some spark plugs and see what their condition is telling you.

 

[Maclin]

Re: test run fail

Looks like gm280 and I posted same stuff at the same time

 

[Howard Sterndrive]

Re: test run fail

the things i did not do to engine before test run, compression test, time engine,

not following. start with those 2 things

 

[rolmops]

Re: test run fail

I had much the same problem last year and it turned out to be bad plugs,which was the last thing I expected.

 

[stratcat88]

Re: test run fail

thanks for the responses guys. i will pull the carb and get it rebuilt. what do ya think about the shifter? thanks again tim

 

[stratcat88]

Re: test run fail

not following. start with those 2 things

i know man but the engine started up so nice that i put the most important diag. tool aside a compression test. will do tonite. thanks

 

[stratcat88]

Re: test run fail

Pumping the throttle 50 times is a key to a lot of your problems. Sounds like your carb is in need of a rebuild. And it also sounds like the choke isn't working either. So before trying again, rebuild the carb and make sure the choke is operational. Then check the compression and timing as well. All these things effect your drivability... Do those things and post back here with your results and numbers... These forums will get you straighten out and running again.

will post tonite, thanks

 

[stratcat88]

Re: test run fail

Looks like gm280 and I posted same stuff at the same time

so what was the problem?

 

[Maclin]

Re: test run fail

Not sure what you just asked, but...

You will have the spark plugs out for the compression test, be sure to include their conditon in your report.

 

[Bt Doctur]

Re: test run fail

i did not do to engine before test run, compression test, time engine, heads rebuilt, new manifolds,risers, plugs,tach,ign.coil, and alot of blood,sweat,and screaming.could use some advice, thanks.

you should have at least:
Done a test run to see what leaks
Check and adjust rockers
Install dist correctly and time engine
Verify firing order

 

[flipbro]

Re: test run fail

Did you mean things YOU'VE DONE to engine?? I hope thats what your saying!!!

 

[stratcat88]

Re: test run fail

Did you mean things YOU'VE DONE to engine?? I hope thats what your saying!!!

yes, did not do compression test or the timing. will do tonite. just dropped off carb to get rebuilt.

 

[s.hadley81]

Re: test run fail

This sound like carb but just like gm280 and Maclin said but w/out knowing compression you really don't know if the motors right but if you get god compression my bet would be tune up and carb rebuild would do wonders providing the motors good first I would compression check then tuneup,timing and look at carb like gm280 said look for accelerator pump working and choke if that don't check out your for lack of a better term pissing in the wind

 

[jackd1023]

Re: test run fail

When you get that carb back, I would run off a "known good fuel source" AKA gallon can. I would also change fuel filter, separator and drain tank.

 

[stratcat88]

Re: test run fail

ok, performed compression test and heres my numbers.#1-95 #3-110#5-95#7-100#2-110#4-110#6-110#8-110. dry.did not do wet test,i know the valves and heads were redone. i dont think I'm going to get 40mph,on plane would make me happy till i can install a new engine. seen chriscraft254 video of his boat on that lake opened up so i know these heavy boats can move. what do you guys think? i also have a new problem, i should start a new thread on that one. thanks again.

 

[Bondo]

Re: test run fail

ok, performed compression test and heres my numbers.#1-95 #3-110#5-95#7-100#2-110#4-110#6-110#8-110. dry.did not do wet test,i know the valves and heads were redone. i dont think I'm going to get 40mph,on plane would make me happy till i can install a new engine. seen chriscraft254 video of his boat on that lake opened up so i know these heavy boats can move. what do you guys think? i also have a new problem, i should start a new thread on that one. thanks again.

Ayuh,.... That's the numbers of a rebuildable Core motor,.... Not a Runner,....

 

[stratcat88]

Re: test run fail

Ayuh,.... That's the numbers of a rebuildable Core motor,.... Not a Runner,....

get what ya pay for bond. gonna slap the rebuilt carb on tonite and thats it. we figured out last nite the boat 5500 and we have put another 7000 into her. love the boat. this summer new engine. thanks

 

[Bt Doctur]

Re: test run fail

"had a couple of leaks,water so i tightend a few hoses and we were good to go. idled out to icw and gave it a little throttle and it was up around 1500 rpms. and that was it."

Did you do the work personally or have a mechanic do the work. With the work listed and in no particular order you should have:
correctly adjusted the pushrods , set #1 at TDC with 0 on the pointer, installed dist pinned to #1 position on the cap. correctly position the spark plug wires like so 1,8,4,3,6,5,7,2 in a clockwise order.
checked cold compression, prefilled fuel sep and carb bowl, test ran the motor for leaks, and adjusted the timing at idle speed, then checked the total advance at 2800 rpm.
Then install the drive and do a water test.
If these were not done your even lucky you got 1500 out of it.